OBSCURATION MYOPIA IN PARTIAL CONGENITAL CATARACT

Abstract

In zonular (lamellar) congenital cataracts, lens opacities occupy specific zones of the lens. These cataracts are the most common type of congenital cataracts in children. They are typically bilateral, symmetrical, and stationary, presenting as ring-shaped opacities between the nucleus and cortical layers of the lens (Bobrova N.F., Vit V.V., 2006). Due to this structural pattern, children usually retain relatively high residual visual acuity, and early surgical intervention is often unnecessary unless visual acuity decreases to 0.25–0.3 or lower (Bobrova N., 2012). The optical outcome of congenital cataract surgery depends on the type of cataract (Bobrova N., 1988), the quality and extent of surgical intervention (e.g., primary IOL implantation after the age of 3 years) (Bobrova N., 2003; Trivedi & Wilson, 2005; Vasavada et al., 2003; Zetterstrom et al., 2005), pleoptic therapy, and the timing of the surgery, which is critical for preventing amblyopia. However, some studies have indicated a potential risk for the development of deprivation myopia as a result of congenital cataracts (Rasooly & BenEzra, 1988). The paper studied the probability of deprivation myopia development on eyes with congenital cataracts in children in cases of untimely surgery. 30 children aged 9 mo-16 years (average 7.09 ± 3.3 years) (51 eyes) with congenital cataracts were examined and operated on. Our study showed that in all age groups of children with congenital zonular non-operated cataracts with low (0.1-0.17) residual visual acuity, even in the youngest (younger than 3 years) group, the axial length increase compared to age norms was noted, which, in turn, determined the myopic refraction formation of the cataract eye. The obtained data may indicate the involvement of different adaptation mechanisms, which leads to the axial length increase. So, it is necessary to perform earlier cataract removal surgery to prevent the deprivation myopia development on the eyes with congenital zonular cataracts.